Lifting-jack



(No Modem l l J. 0. JOYCE.

LIFTING JACK.

No. 305,392. i Patented sept. 16, 1884.

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Arnivr JACOB o. Joven, on DAYTON, OHIO.

SPECIFICATION forming part of Letters Patent No. 305,392, dated September 16, 1884.

Applicationltled August 7, 1884. (No model.)

To all whom, it may concern/.-

Be it known that I, JACOB O. JOYCE, a resident oi' Dayton, in the county of Montgomery and State of Ohio, have invented certain new and useful Improvements in Lifting-Jacks, of which the following is a specification.

I have invented an improved lifting-jack which is primarily designed as a track-jack5 but it may be advantageously used for other purposes.

The object of my invention'is to provide a ing-pawl in position in the housing. Fig. 6 is` an elevation of the housing on the plane ot' the oppositelever. Fig. 7 is a plan view of the lifting-bar in a modified frame; Fig. 8, an elevation of the lifting-bar and foot.

Fig, 1 represents my improvement as applied to a trackljack which is provided with two legs, A A', which span the track to be lifted. r

a represents the foot attached to the legs A A. v

b b c c, Fig. 3, represent wings or ribs cast on and with the legs A. The object of making the legs in this -lshape is to increase the strength of the legs or posts.

rIlhe feet a are preferably made circular, or with a broad base, so that the jack may rest firmly on its base.

B represents the housing in which the pawls work. It is cast on and with the frame. One side is left open, so as to provide means of easy access to the pawls.

C represents a guide pierced with a hole of` the proper shape to t the bar.

D represents a similar guide at the upper end of the ,frame above the housing. These guides may be at any convenient point in the frame above and below the pawls.

E represents a liftingbar,which is shown as made square, which is one feature ot' my invention. H p i F represents a link pivoted between ears n, which project up from the housing.

d represents a pivot hingiug link F to the ears a n.

G represents a liftinglever, which is preferably bifurcated, the forks I I oli' which receive the link F.

K represents the pivot or fulcruin upon which the lever G moves.

L represen ts a pivot, which hinges the pawl M to thci'orks I of the lever. The pawl is pierced with a square opening,which is slightlylarger than the area of the lii'tingvbar E,which passes through the same.

N represents the holding-pawl, which rests loosely in slot O, pierced through the housing.

O represents a stein formed on pawl N and projecting through the slot O.V

By making the bar square and the pawls with similarly-shaped orifices m, I obtain important results, as the pawl lifts or holds by the friction due to the angular positionof the pawl relative to the plane of the lifting-bar.` Much moresurface or metal of the bar is `in frictional contact with the sides of the pawl when the same is made polygonal or manysided than when made round.4 Hence the lifting or holding oi the pawls is much more positive in connection than when a round bar and similarlyshaped the action ofthe jack much more positive, as well as more durable. The orifices in the pawls M N are pierced through at right angles to their faces, so that when the edges become worn by frictional contact with thelifting-bar these pawls can be reversed and new edges brought into use, greatlyincreasing the `pawl. These polygonal or square bars may be employed with a foot, as represented in Figs. 7 and 8.

J represents the ordinary foot, connected to the bar E, projecting from the angles of one corner, as shown in Fig. 7. This makes a much stronger foot or bar, as the strain upon the bar is diagonal from corner to corner, and hence a much lighter and smaller bar may be used when it is made square, with the foot connected, as here shown, than when the bar is made round.

pawls are used, making the nf@ of 9o roo similar objects, and to be readily detached by the foot.

' 5 t represents a hook-jaw formedV upon the bar E.

U represents a hinge-jaw attached to the stationary jaw t by a pivot, r. The jaw U is preferably bifurcated or forked, one prong of 1o which fork passes upon each side of the bar E; or the jaws may be made in the ordinary form. p A

p represents an arm rigidly attached to the jaw U, and passing out a sufficient distance beyond the pivot r, so as to form a fulcrum or lever, so that the jaws maybe released by applying the foot to the lever p.

I have devised an improvement for releasing the holding-pawl, or holding it out of use.

2o It is represented in Fig. 1 by lines B S T. S represents ears or studs projecting up from the base of the housing B, under the outer end of lifting-pawl N. B represents a lever pivotedto said stud; T, a cam or upturned end.

2 5 When lever B is turned down, the cam T sstrikes the end of pawl N and raises it from contact with the bar E. This device is convenient for lowering a load by ymeans of a lever and operating-pawl N in connection there- 3o with. The cam-lever T B is preferably so constructed that whenlthe ca m D is raised to hold the pawl N it is past the center, so as to form a lock and prevent the pawl coming into use until the lever B is raised.A I do not de- 3 5 sire to limit myself to this particular form of lock for holding the pawl N out of engagement with the bar E.

The device is shown as having the lever G,

V rially affecting the operation of the pawls and lever. By having the space in the housing materially greater than the length of the pawl, and one side of the housing open, the Vpawls may be readilyv inserted and removed when y 5o the lifting-bar is dropped out of its place,and

this is afeature of my'invention.

I am aware that alifting-bar annular in crosssection has been combined with lifting frictionpawls having annular orifices for the bar, and such I do not claim.

the housing b, containing the operative parts,

I claim- 1.The combination, in a lifting-jack, of the bar E, angular in crosssection,with thefrictionpawls `M N, having angular openings for the bar, substantially as and forthe purposes described.

2. In combination with the frame of a lifting-j ack, a housing, B, provided with slots L l. and O, Fig. 5, through which the pawls work, substantially as specied.

3. The frame of alifting-jack,composed substantially of the posts A A', provided with projecting wings BB CC, and feet a, and with mounted upon the top of the posts, substan- 7o tially as specified. o j.

' 4. In combination with the lifting-bar E, stationary jaw t, and pivot-jaw U, provided with the projecting arm p for releasing the clutch of the jaws, substantially as specied.

5. In combination with the polygonal bar E, the foot J, secured to the diagonal corner of the bar, substantially as specified.

6. Incombination with the lever E, hinged to the frame of Kthe lifting-jack, the pawl M, pivoted to said lifting-lever and provided with the polygonal-shaped opening for clutching a similarly-shaped lifting-bar, substantially as specified. l v

7. In combination with the frame of aliftingjack, a housing, B, pierced with .the orifice O, which supports the stem ofthe clutchpawl N, substantially 'as specified.

8. The housing B, secured to the frame of the lifting-jack, and of greater width inthe opening than the length of the pawls, and pierced with orifices O for supporting 'the stem of pawl N, substantially as specified.

9. In combination with the lever Gandlifting-bar E, the reversible pawl M, pivoted to the lever and engaging the li.ftingbar,substan tially as specified.

l0. In combination with the housing` B, thev reversible pawl M, supported therein and engaging the lifting-bar, substantially as and for the purpose specified,

In testimony whereof Ihave hereunto set my hand. l

JACOB O. JOYCE.

Witnesses:

EDW. BOYD, J oHN L. H. FRANK. 

